Magnetically coupled recorderindicating instrument



July 5, 1949. E. M. SMITH ETAL MAGNETICALLY COUPLED RECQRDER-INDI CATINGINSTRUMENT Filed Oct. 18, 1944 2 Sheets-Sheet 1 3110mm: AND EDWARD M.SMITH B5 DONALD P. BERG FIG.

July 5, 1949. k E. M. SMITH ETAL 2,475,573

MAGNETICALLY COUPLED RECORDER-INDICATING INSTRUMENT Filed Oct 18, 1944 2Sheets-Sheet 2 cl 0 0K LL \l/ Bnventor:

I EDWARD M. SMITH DONALD P. BERG FIG. 6 01 fl g v K 2 their CfltornegPatented July 5, 1949 MAGNETICALLY COUPLED RECORDER- INDICATINGINSTRUMENT Edward M. Smith, Cleveland, and Donald P. Berg, ClevelandHeights, Ohio, assignors to Bailey Meter Company, a corporation ofDelaware Application October 18, 1944, Serial No. 559,152

4 Claims.

Our invention relates to apparatus for measuring variable quantities,qualities, conditions, positions and the like, and particularly toproviding a visual indication by means of a pointer positioned relativeto a scale or graduated member. Our invention also relates to anindicating means to be used in conjunction with a recorder to indicateat a distance the value of the condition which is being recorded on achart by a recording pen or stylus.

One object of our invention is to provide a large indicator pointer,pivoted co-axial with a time revoluble circular recorder chart, sweepingover the chart without interfering with the pen or pens recordingthereon and cooperating with a circular scale surrounding at least aportion of the recorder chart.

A further object is to provide an indicator pointer cooperating with ascale located concentrically with the chart driving hub and wherein thepointer is magnetically held by means extending through the chartdriving hub from the rear of the chart and chart support.

Another object is to provide an indicator pointer positioned coaxiallywith the chart and arranged to be lifted out of the way for changing thechart and to be returned to driving engagement without loss of properindicating relation.

A further object is to provide an indicator pointer driven through thechart hub in such a manner that the chart may be removed and replaced atwill without disconnecting any mechanical connections between thepointer and its driver and so that synchronism therebetween will not bedisturbed regardless of how often the chart is changed.

A still further object is to provide an indicating-recording instrumentof the circular chart type so constructed that the. chart may readily bechanged without disturbing the indicator mechanism or varying therelative position between the value recorded and the value indicated bythe indicating pointer.

Another object is to provide means for lifting the indicator pointer outof the way while changing the chart and simultaneously lifting the penor pens away from the chart.

A particular object is to provide a magnetic and mechanical couplingbetween the pointer and its driver so arranged that when the pointer isplaced in axial juxtaposition with its driver the pointer will besynchronized with the driver for proper indication.

The type of measuring instrument to which our invention is particularlydirected may be an' indicator or an indicator-recorder of quantity,quality, condition, position or such variable. For example, theinvention may be utilized in a measuring instrument adapted to indicateand record the rate of flow of a fluid, temperature, pressure, or anysimilar variable. For an understanding of our invention, its advantagesand the specific objects obtained through its use, reference should behad to the accompanying drawing and to the specification describing thesame.

In the drawings:

Fig. 1 is a front elevation (with the cover door partially cut away) ofan indicating-recording instrument embodying a preferred form of ourinvention.

Fig. 2 is a sectional elevation of a portion of Fig. 1, along the line2-2, in the direction of the arrows.

Fig. 3 illustrates a portion of Fig. 2 with the parts thereof in anotheroperating position.

Figs. 4, 5 and 6 are different views of a portion of Fig. 1.

Referring now to Fig. 1, we show therein a measuring instrument of theindicating-recording type having a case I to which is hinged a frontdoor 2. The door is provided with a glass 4 comprising a window throughwhich may be viewed the record chart 5, the recording pen 6 and anindicator pointer 1. Around the periphery of the glass window 4, andcarried by the door 2, we provide an indicator scale 8 with which theend of the movable pointer 1 cooperates to indicate the value of thecondition being measured so that a visual indication of the conditionmay be had at a considerable distance from the instrument.

The door 2, hinged as at 3, may be opened to provide ready access to thepointer, recording pen, and chart. Furthermore, the opening of the door2 provides access to a hinged chart mounting plate 9 hinged as at It. Inthe particular construction being described the door 2 opens toward theright, whereas the back plate 9 opens toward the left. Mounted on therear of the door 5 is a chart drive clock I I. Some of the measuringapparatus for positioning the pen 6 may be carried on the rear of theback plate 9, or in any event the opening of the back plate exposes thecomplete interior of the meter case I.

Mounted on the back plate 9 we provide a mechanism generally indicatedat l2 having an extension arm is joining the pointer carrying mechanismand having a further extension ll providing a pen lifter. Figs. 4, 5 and6 show the mechanism l2 in greater detail and in different positions ofoperation.

Referring now in particular to Figs. 2 and 3, we show therein that theclock I I, supported from the back plate 9, drives through suitablemeans (not shown) a chart rotating spindle l5. Usually the tubularspindle l5, and chart 5, are adapted to make one complete revolution intwenty-four hours. Fastened to, and rotated by the spindle |5, is amember I6 having a circular front surface fiush with the front of theback plate 9 and a forwardly extending hub ll of an outside diameter toreceive the central hole of the chart 5. The member I B is provided witha plurality of forwardly projecting sharp pins It for piercing the chart5 and holding the same for rotation by the member 3. In other words, thechart 5 is centered over the hub I'I, properly turned by hand until thepen 6 indicates the proper time ordinate and then the chart 5 isdepressed over the pins l8 by means of bearing race 20 whereupon it liesflush on the front of the back plate 9. .Thereafter rotation of thespindle 5 and member It will rotate the chart 5 upon the face of theback plate 9. Fig. 3 shows the position of the chart 5 just described.

Positioned by and with the arm I3 is a member |9 adapted to be movedthrough an are about shaft 38 toward and away from the chart receivinghub Shrouded by the member I9 is a rotatable member 20 having a skirt 2|engageable with the chart 5 n the member |6 to grip the chart betweenthe members 20 and It. In the skirt 2| is an annular groove 22 toreceive the points of the pins I8. Thus when the assembly comprising themembers I9 and 20 is in its position (Fig. 2) furthest toward the right,the chart 5 is firmly gripped between the skirt 2| and the member ISwith the pins l8 puncturing the chart. Thereafter rotation of the member[6 will drive the chart angularly, and with it the member 20; the memberl9 remaining stationary.

By the description so far it will be apparent that means are providedfor rotating the chart 5 at a uniform speed by any common clockwork. Thechart is normally rotated once in twentyfour hours, and thereupon thepen 5 draws the record.

For indicating the value which the pen 6 is recording, or other values,we provide that the pointer 1 be angularly positioned relative to thescale 8. A sector 23 drives a pinion 24 rotating a shaft 25 extendingthrough the tubular spindle I5 and the member Hi, to rotate an extensionshaft 25' and the pointer As an important feature of our invention weseparate the pointer driving means into two parts 25, 25 so that thepointer, member l9, and shaft part 25' may be moved away from the charthub I! (Fig. 3) when it is desired to change charts.

Near the end of the shaft 25 we provide a cylindrical magnet 26 having asloped end surface 21. On the end of the shaft 25 we provide a matingcylindrical magnet piece 25' having a sloped end surface 28. The magnets26 and 26' are oppositely magnetized, i. e. (for example) the tip of theslope 21 may be a south pole and the heel of slope 21 may be a northpole, while the heel of the sloped surface 28 may be a north pole andits tip a south pole. Thus with the assembly as shown in Fig. 2 themagnets are in complementary position. Through the center of the magnet26 we extend the shaft 25 to form a guiding end 29 receivable in thebore 30 of the magnet and of the shaft 25'.

In normal operating position (as shown in Fig. 2) the guiding end 29 iswithin the tubular shaft 25, whereas the mating surfaces 21, 28 aremagnetically locked together. A particular feature of the presentinvention is that should the pointer l, shaft 25, and magnet 26' bemoved angularly while away from the matin surface 21 (Fig. 3) they willautomatically become aligned and in driving synchronism when closedtogether as shown in Fig. 2. As the mating surfaces 21, 23 approach eachother the magnetic force will tend to align them in true complementwhile the magnet 26 is guided on the portion 29. Such angular movementcaused by the magnetic attraction between the two opposite poles willmove the pointer l to its proper indicating position (relative to thescale 8) in accordance with the position of the driving means 23, 24.Thus at any time that the surfaces 21, 28 are moved apart, as in Fig. 3,the possibility of returnin the parts into driving engagement with thepointer I reading incorrectly is eliminated.

Inasmuch as normal movement of the pointer 1 and member I9 is notaxially in line with the shaft 25 but is over a lon radius are aboutshaft 38 we slightly enlarge the bore at its emergence through the face28 so that the guiding portion 29 will positively enter the bore 30regardless of the position in angular movement of the magnet 26' andpointer I. It will be observed that shaft 25' is purposely loose inmember l9 so that in operating position (Fig. 2) member [9 does not forma bearing for 25' and there is no contact between members l9 and 25 inthe pointer driving position. The free hearing between I9 and 25', aswell as the relief of bore 30 (right-hand entrance Fig. 3) permit radialand axial motion of 25' when engaging with shaft end 29 while member l9moves through an arc. The free bearing also eliminates necessity ofmaintaining exact coincidence or axial alignment of IS, 25 and 25.

Through the agency of the assembly I 2 and the arm |3 the pointer memberI!) and magnet 26 are moved away from the chart 5 and magnet 28 (seeFig. 3). Figs. 4, 5 and 6 show in greater detail the construction of theassembly l2.

An enclosing housing 3| takes the general shape of an inverted cup openat the bottom. In the top is an elongated slot 32 in which is movable arelease lever 33 substantially filling the opening 32 in the positionshown in Figs. 1 and 6 corresponding to the assembly Fig. 2. Thepositions of the parts in Figs. 4 and 5 correspond to Fig. 3.

Mounted on the back plate 9 is a bearing support member 34 to which ispivotally mounted a cam 35 integrally formed as an extension of thelever 33. The member 34 also has bearing pieces 36, 3! in which isjournaled a shaft 38 whose ends extend beyond the bearings 36, 31 andare riveted or otherwise fastened as at 39 (Fig. 1) to the housing 3|.Thus the housing 3|, and arm |3 carried thereby, pivots around themembers 36, 31 through the agency of shaft 38.

Fastened to the housing 3|, as by the rivets 40, is a leaf sprin 4|whose opposite end engages the arm Hi. This leaf 4| serves primarily asa safety device to prevent damage to arm l3 if for any reason theassembly fails to seat normally. It also serves the purpose of confiningthe cam 35 between itself and the upper interior of the housing 3|, thusputting a slight braking action upon the cam to hold the assembly in anygiven cam position limited by movement of the lever arm 33 withintheslot 33.

It will be seen that the position of the members shown in Fig. 6dictates a position of the arm I3 most adjacent the chart and back plate9 and results in the showing of Fig. 2. If it is now desired to lift thepointer I, the member I9, the pen lifter I4, and the pen 8 away from thechart 5 so that the chart may be removed from the pins I8 and hub I1 andreplaced by another chart or rotated angularly for correct timing, thenthe hand lever 33 is moved to the position shown in Figs. 4 and 5.Viewing Fig. 5, a clockwise lifting of the lever 33 moves the cam 35 inclockwise rotation, thus tending to raisethe housing 3| incounterclockwise rotation around its pivots 39 of shaft 38. Such angularpositioning of the housing 3i elevates the end of the arm I3 which isattached to the member I9, thus lifting the member I9 and associatedparts away from the chart 5. By the same motion the pointer I is movedout of the way, as is the pen lifter I4 carrying the pen 6. Thereafterthe chart 5 is free for removal from the hub II and pins I8.

After a new chart has been placed on a hub I1 and properly located as totime ordinate it is depressed onto the pins I8. The arm 33 is moved incounterclockwise rotation, thus moving the member I9 toward the backplate 9. The shaft extension 29 enters the opening 30, the magnetsurfaces 21, 28 move into alignment and are magnetically coupled so thatthe magnet 26 drives or positions the pointer I. If, while the parts areapart as in Fig. 3, thepointer I is moved out of proper synchronism withthe driving magnet 26, then when the faces 21, 28 approach each otherthe combination of magnetic attraction between the surfaces 21, 28 andthe conformation of said surfaces results in an angular movement of themagnet 26', and pointer 1, until the magnet faces 21, 28 are properlylined up and sea or couple together.

In general, when the arm I3 and parts carried thereby are moved towardthe chart, the axial alignment of parts is mechanical, the radialsynchronization is both magnetic and mechanical,

and thereafter they are magnetically locked inv driving position.

From the foregoing description it will be apparent that we have providedan improved means for positioning an indicator pointer, an improvedmeans for moving a pointer and pen out of the way when it is desired tochange charts and an improved means for synchronizing the pointer whenreturned into drivin position. Other features and advantages will beapparent from a study of the disclosure.

Reference may be had to our copending continuing application S. N.61,156, filed November 20, 1948, which claims certain features of ourpresent invention disclosed herein.

What we claim as new, and desire to secure by Letters Patent of theUnited States, is:

1. In a recording-indicating instrument having a chart and means formaking a record on the chart, the combination comprising a first shaftmember supported for rotation in response to changes in a value to bemeasured, a chart mounting plate coaxially rotatable relative to andabout said first shaft member, a second shaft member carrying anindicator for showin the angular position of said first shaft member,carrying means rotatably receiving said second shaft member, meanssupporting said carrying means and second shaft member for bodilymovement toward and away from the first shaft member and the chartmounting plate to clamp the chart to said plate, and a pair of magneticcoupling elements fixed respectively to the adjacent ends of said firstand second shaft members and arranged for direct engagement when thecarrying means is moved toward the chart mounting plate, said magneticelements being formed with inclined complemental end faces each havingtwo poles of opposite polarity and constituting the elements of amechanical coupling opposing relative angular movement of said shaftmembers when said faces are in direct engagement.

2. In a recording-indicating instrument having a. chart and means formaking a record on the chart. the combination comprising a first shaftmember supported for rotation in response to changes in a value to bemeasured, a chart mounting plate mounted on said first shaft member forrotation relative thereto, a second shaft member carrying an indicatoron its outer end portion for showing the angular position of said firstshaft member, carrying means receivin said second shaft member, anannular chart clamping member rotatably mounted in said carrying meansin spaced relation to the inner end portion of said second shaft member,means supporting said carrying means, second shaft member and chartclamping member for bodily movement in a predetermined path toward thefirst shaft member and the chart mounting plate to clamp the chart andaway therefrom to provide access to said mounting plate, and a pair ofmagnetic coupling elements fixed respectively to the adjacent ends ofsaid first and second shaft members, said magnetic elements being formedwith inclined complemental end faces each having two poles of oppositepolarity and constituting the elements of a mechanical coupling opposingrelative angular movement of said shaft members when said faces are indirect engagement.

3. In a recording-indicating instrument having a chart and means formaking a record on the chart, the combination comprising a first shaftmember supported for rotation in response to changes in a value to bemeasured, a chart mounting plate mounted on said first shaft member forrotation relative thereto, a second shaft member carrying an indicatorfor showing the angular position of said first shaft member, carryingmeans loosely receiving said second shaft member for rotation therein,means supporting said carrying means and second shaft member for bodilymovement in a predetermined arcuate path toward and away from the firstshaft member and the chart mounting plate to clamp the chart to saidplate, and a. pair of magnetic coupling elements fixed respectively tothe adjacent ends of said first and second shaft members and arrangedfor direct engagement when the carrying means is moved toward the chartmounting plate, said magnetic elements being formed with inclinedcomplemental end faces constituting the elements of a mechanicalcoupling opposing relative angular movement of said shaft members whensaid faces are in direct engagement, one of said end faces having acentral projecting guiding portion and the other of said end faceshaving a central bore withan enlarged opening for receiving said guidingportion as the magnets are moved into direct engagement.

4. In a recording-indicating instrument having a chart and means formaking a record on the chart, the combination comprising a first shaftmember supported for rotation in response to changes in a value to bemeasured, a chart mounting plate mounted on said first shaft member forrotation relative thereto, a second shaft member carrying an indicatorfor showing the angular position of said first shaft member, car-- ryingmean loosely receiving said second shaft member for rotation therein, anannular chart clamping member rotatably mounted in said carrying meansin spaced relation to the inner end portion of said second shaft member,means supporting said carrying means, second shaft mem ber and chartclamping member for bodily movement in a predetermined arcuate pathtoward and away from the first shaft member and the chart mounting plateto clamp the chart to said plate, and a pair of magnetic couplingelements fixed respectively to the adjacent ends of said first andsecond shaft members and arranged for direct engagement when thecarrying means is 20 faces are in direct engagement, one of said endfaces having a central projecting guiding portion and the other of saidend faces having a central bore with an enlarged opening for receivingsaid guiding portion as the magnets are moved into direct engagement.

EDWARD M. SMITH.

DONALD P. BERG.

REFERENCES CITED The following referenlces are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,174,787 Wilkinson Mar. 7, 19162,074,116 Stein Mar. 16, 1937 2,074,117 Ross Mar. 16, 1937 2,124,832Schofleld July 26, 1938 2,226,287 Miller Dec. 24, 1940 2,244,653 MeerJune 2, 1941 2,288,688 Dubilier July 7, 1942 2,307,912 Bean et al Jan.12, 1943 2,353,740 Malone July 18, 1944 2,417,339 Woolley Mar. 11, 1947

